Thickening of solutions



2,189,803 7 I w or SDLUTIONS Morris 28. Katzman and l ra 5. Gahn, Chicago,

cago, ill.

ill assignors to The Emulsol Corporation, Ghi- No Drawing. Application December 18, 1937, Serial No. 180,662

20 Claims.

This invention relates to the thickening of solutions and is particularly concerned with the thickening of aqueous solutions of so-called interface modifiers.

In dealing with solutions of interface modifying agents which are known to the prior art, it frequently becomes highly desirable to increase the thickness, consistency or viscosity of said solutions. As an example, preparations have been produced in accordance with prior art teachings wherein an interface modifying agent having sudsing and detergent powers is dissolved in a suitable solvent such as water or organic solvents such as alcohol or aqueous-organic solvents such as mixtures of water and alcohol. For meeting the demands of certain classes of trade, it is highly advisable to provide a product having a relatively heavy consistency or an enhanced thickness. While an increase in thickening may, in certain cases, be accomplished by increasing the concentration of the interface modifying agent in its solvent, this becomes impracticable in most cases since the interface modifying agents are frequently soluble to only a limited extent in the particular solvent preferred to be used. In addition. the increase in the concentration of the interface modifying agents, aside from other disadvantages emanating from such practice, is usually uneconomic since the degree of enhancement tageous in many instances to increase the thickness,-consistency or viscosity of such and similar solutions to facilitate the handling thereof and minimize the loss duringpouring and the like from bottles or similar containers or receptacles. Other advantages accrue from the present invention into which it is not necessary to go into detail.

It is, accordingly, an important object of the present invention to increase thickness or viscosity of solutions of interface modifying agents in a relatively simple and inexpensive manner.

A further object of the invention is to increase the thickness or viscosity of aqueous solutions of interface modifying agents which have high sudsing and detergent properties, which solutions may be'employed for the same cleansing and washin; purposes as are ordinary soaps.

Other objects and features of the invention will become apparent as the detailed description of the invention proceeds.

As a result of considerable research work, a

When poured from a bottle.

large class of thickening agents has been discovered of general utility for thickening solutions of interface modifiers, and of marked uitility for thickening solutions, particularly aqueous solutions, of interface modifying agents having good sudsing and detergent properties. These thickeners may be characterized as salts o1 organic nitrogenous bases, notably salts of such bases with water-soluble acids. Particularly useful are the salts of the alcohol amines, and of unusual utility are the salts of mono-ethanolamine, especially monoethanolamine sulphate.

In place of monoethanolamine, other organic nitrogenous bases may be employed as, for example, alcohol amines and alkylolamines including diethanolamine, triethanolamine, propanolamines, butanolamines, pentanolamines, hexanolamines, glycerolamines, dibutyl ethanolamine, di-

ethanol ethyl amine, cyclohexyl ethanolamine, alkylol polyamines such as alkylol derivatives of ethylene diamine, mono-methyl mono-ethanolamine, diethyl monoethanolamine, 1-amino-2, 3- propanediol, 1,2-diamino propanol; alkylamines such as butylamine, dimethylamine, ethylene diamine, diethylene triamine, triethylene tetraamine, mono-methyl ethylene diamine, monoetliyl diethylene tetra-amine, aromatic and heterocyclic bases such as pyridine, quinaldine, piperidine, methylpyridine, and homologues and derivatives thereof, quaternary ammonium bases or hydroxides such as tetra-methyl ammonium hydroxide, tetra-ethyl ammonium hydroxide, quaternary ammonium bases with dissimilar alkyl radicals such as methyl-triethyl ammonium hydroxide, propyl-trimethyl ammonium hydroxide, mixtures of any two or more thereof, and the like. It will be understood that these organic nitrogenous bases may be employed in pure, impure or commercial form such as, for example, commercial triethanolamine which contains minor proportions of mono-and dl-ethanol amine.

As stated, these organic nitrogenous bases are employed in the form of their salts such as sulphates, phosphates, nitrates, acetates, chlorides, bromides, iodides, borates, lactates, citrates, tartrates, and the like or mixtures of any two or more thereof. known in the art, for example, by neutralizing the base or mixtures of bases with the equivalent amount of acid or any desired mixture of two or more acids. For example, monoethanolamine acetate may be prepared by mixing equal molecular quantities of monoethanolamine and glacial acetic acid. The glacial acetic acid is added drop by drop to the monoethanolamine while constantly stirring the latter, the flask or the like containing the monoethanolamine being surrounded by an ice bath to insure that the temperature does not rise .too high andtoo rap dly. The

The salts may be made in ways,

ethanolamine sulphate, diethanolamine acetate,

triethanolamine acetate, 1-amino-2, 3-propanediol acetate, 1,3-diaminopropanol acetate, monoethanolamine phosphate, triethanolamine phosphate,

ethylenediamine sulphate, butylamlne acetate, and the like. 1

It is convenient to prepare a solution of the thickener and add it in the desired amountsto the interface modifying agent solution although the manner of incorporation is optional and may be accomplished in various ways as, for example. in situ during the preparation of the solution of the interface modifying agent. Since, in the main, aqueous solutions of interface modifiers are employed, the thickeners utilized in such solutions will be water-soluble. It will be understood that in all cases the thickener must be soluble in the solution of the interface modifier in which it is employed.

The interface modifying agents whose solutions may be thickened by means of the compounds disclosed hereinabove are generally characterized by the presence of at least one higher molecular weight lipophile group containing preferably at least eight carbon atoms, preferably although not necessarily, aliphatic in character, and by the presence of at least one hydrophile or hydrophilic group, preferably in the form of an oxygenated sulphur, phosphorus or boron radical, particularly sulphur in the form of sulphate or sulphonic acid radicals, although, as will be seen, the hydrophilic group is not so limited Preferably, the lipophile and hydrophile groups are in a state of balance whereby the resulting compound has the property of reducing the spattering of margarine when used for frying. This concept of balance of lipophile and hydrophile groups is treated in considerable detail in the patent to Benjamin R. Harris, No. 1,917,250, issued July 11, 1933 and need not here be elaborated upon further. While this "balance may be determined empirically by means of a margarine frying test, as described in said patent, those skilled in the art will, in most cases, readily be able to predict the existence of balance from merely an inspection of the molecule of the compounds themselves. As a general rule the hydrophile and lipophile groups should preferably be at the ends or extremities of the molecule as, for example, in the case of lauryl sodium sulphate wherein the lauryl group or, in other words, the lipophile group, is present at one end .of the molecule, and the sulphate or hydrophile group is present at the other properties. This aspect of the invention will be- .come more apparent as the description proceeds.

It will be understood that the term lipophile group includes groups having a definite affinity lauryl alcohol, myristyl alcohol,

for oils and fats and comprises, for example, alkyl, aralkyl, aryl, ether or ester groups containing preferably at least eight carbon atoms. The lipophile group possesses predominantly hydrocarbon characteristics and, in general, is derived from triglyceride fats and oils, waxes, mineral oils, other hydrocarbons, and the like.

In contra-distinction thereto, the term hydrophile group or hydrophilic group includes groups which possess an affinity for water and aqueous media. As examples of such groups may be mentioned the following: hydroxyl, hydroxylcarboxylic, sulphate. suiphonic, phosphate, pyrophosphate, tetraphosphate, borate, lower molecular weight sulpho-carboxylic acids such as sulphoacetates, sulphopropionates, etc., and quaternary ammonium and other hydrophilic nitrogenous groups.

Among the interface modifying agents whose solutions may be thickened in accordance with the present invention are organic substances hav,v

ing balanced lipophile and hydrophile groups, the lipophile group containing at least eight carbon atoms and the hydrophile group comprising a radical selected from the class consisting of oxygenated sulphur, oxygenated phosphorous, and oxygenated boron inorganic acid radicals.

One sub-class thereof, several members of which have excellent sudsing, foaming, frothing, lathering, and detergent powers, comprises the higher molecular weight alcohol sulphates and sulphonates. The alcohols from which these sulphates and sulphonates may be prepared include the following: aliphatic straight chain and branched chain alcohols such as octyi alcohol. nonyl alcohol, decyl alcohol. undecyl alcohol. cetyl alcohol. oleyl alcohol, linoleyl alcohol, stearyl alcohol. ricinoleyl alcohol, palmitoleyl alcohol, melissyl alcohol, ceryl alcohol, carnaubyl alcohol myricyl alcohol, branched chain octyl, decyl, dodecyl. tetradecyl, hexadecyl and octadecyl aliphatic alcohols as, for example, Z-ethyl hexanol-l, 2-n butyl octanol-l, 2-butyl tetradecanol-l, and, in general, the higher molecular weight saturated and unsaturated aliphatic straight chain and branched chain alcohols. Preferably, the alcohols which are utilized are those corresponding to the fatty acids occurring in triglyceride oils and fats of vegetable or animal origin, natural, or hydrogenated, such as cornoil, cottonseed oil, sesame oil, coconut oil, palm kernel oil, sunflower seed oil, lard, tallow, soya bean oil and the like, those alcohols containing from 12 to 18 carbon atoms being preferred. Other alcohols which may be employed are the cyclo-aliphatic or alicyclic alcohols such as the sterols, as, for example. cholesterol. iso-cholesterol, phytosterol, sitosterol, hydroaromatic alcohols such as abletol, and such unsaturated alcohols as linalool, citronellol, geraniol and the like. Also included within the class of alcohols which may be employed are such compounds as the hydroxy and alpha-hydroxy higher aliphatic and fatty acids as, for example. ricinoleic acid, alpha-hydroxy stearic acid, alpha-hydroxy lauric acid, di-hydroxy stearic acid, i-hydroxystearic acid, aIpha-hydroxy. palmitic acid, and the like, as well as esters of hydroxy-fatty acids, such as ethyl ricinoleate. castor oil, butyl elpha-hydroxystearate, cetyl hydroxystearate, and the like.

The term alcohols as-employed herein, is intended to include alcohols which may or may not contain other groups such as carlioxylic, halogen,

sulphonic, sulphate, or other radicals. The alcoilmitic acid ester of mannitol, dicaproic acid' .ter of maltose, mono-octyl ether of sorbitol.

onolauryl ether of pentaerythritol, monolauric.

It; is. of course, obvious that thealcohols from" hich the sulphates and sulphonates may be proiced may be prepared in accordance with any :sired method. For example, many of these cohol's may be prepared by the so-called Bouaault and Blane method or, alternatively, by the lduction or catalytic reduction with hydrogen natural or hydrogenated animal or vegetable its and oils. or mixtures thereof. in accordance lth well known practices. Again the alcohols ,ay be derived from synthetic processes such as 7 the oxidation of hydrocarbons or may be preired by saponification of waxes and the like. lternatively, they may be prepared by reduction aldehydes or by the Grignard reaction.

It is likewise apparent that mixtures of the uregoing or other alcohols may be utilized in the reparation of the sulphates and sulphonates as. rr example, the mixture of alcohols resulting pm the hydrogenation of coconut oil or the free My acids of coconut oil. Lauryl alcohol comrises about 45% of the total alcohol mixture, the amaining alcohols running from C3 to 0.15. gain, mixtures of alcohols such as are present in ie so-called sperm oil alcohols, as well as those resent in wool-fat, may equally eflicaciously be tilized. 'Indeed, these higher molecular weight lcohols are generally offered on the market in ie form of mixtures of different alcohols. If dered, for any specific purpose. special fractions 'hich predominate in a certain particular higher iolecular weight alcohol may be utilized or, if so esired, the products may be prepared from a ngle, substantially pure alcohol.

These sulphates and sulphonates, described ereinabove, may, in general, be represented by 1e formula [RXlnY wherein R is a radical :vntaining a hydrocarbon chain of at least eight arbon atoms, X is a sulphuric or sulphonic group resent at on near an extremity of the radical apresented by RWY is a cation or the radical of salt forming compound, and n is a small whole umber, at least one.

In a still more specific aspect of this sub-class f compounds, the sulphates may be represented y the formula l'R-OSO3];Y wherein R :presents the residue of a normal primary alcohol cntaining from 8 to 18 carbon atoms, Y repreents a cation or the residue of a salt forming ompound such as sodium, triethanolamine or the kc, and n is a small whole number, at least one.

The sulphates and sulphonates described are preferably utilized in the form of salts and, in their preparation, the acid sulphuric ester or sulphonic acid may be neutralized, in whole or in part, with suitable anti-acid materials. In this connection, considerable latitude and modification may be exercised. In general, inorganic as well as organic anti-acid agents may be employed. Examples of such agents which may be used satisfactorily are bicarbonates of the alkali metals, potassium hydroxide, sodium oxide, sodium carbonate, ammonium hydroxide, ammonia gas, po-

tassium stearate, sodium stearate, magnesium oxide, magnesium carbonate, organic anti-acid nitrogenous materials including amines and alkylolamines such as, for example, mono-. diand triethanolamine and mixtures thereof, propanolamines, butanolamines, polynitrogenous amine such as ethylene diamine, ethylene triaminc and the like, pyridine, piperidine, quaternary ammonium bases such as tetra-ethyl ammonium hydroxide, tetra-methyl ammonium hydroxide, and in general, primary, secondary and tertiary amines substituted or not with other radicals'such as hydroxy groups, and the like. It will be understood that by the term cation, as used throughout the specification and claims, is meant hydrogen and such other elements as are mentioned herein, and. in general, atoms or radicals which are regarded as bearing a positive charge or capable of replacing acidic hydrogen. The reaction products may be neutralized to methyl orange, litmus or phenolphthalein. As a general rule, if the salts of the reaction products are employed, it is preferred to use the sodium, potassium, ammonium, triethanolamine, quaternary ammonium, or other relatively highly soluble salts.

The sulphates and sulphonates disclosed hereinabove are described, among other places, in the following United States Patents 1,897,741, 1,968,- 793. 1,968,794. 1,968,796, 1,968,797, 2,006,309, 2,023,387, 2,052,027, and 2,077,005.

Another sub-class of interface modifying agents whose solutions may be thickened are those compounds which correspond to the higher molecular weight alcohol sulphates and sulphonates described hereinabove but wherein the hydrophile group comprises oxygenated phosphorus instead of oxygenated'sulphur. Among these compounds may be mentioned lauryl pyrophosphate, palmityl orthophosphate, sodium lauryl tetraphosphate, stearyl triethanolamine orthophosphate, oleyl monoethanolamine pyrophosphate, monolauric acid ester of diethylene glycol tetraphosphate, monoethanolamine salt, and the like. As in the case of the sulphates and sulphonates described previously, it is generally preferred to employ the oxygenated phosphorus derivatives in the form of their alkali, ammonium, or nitrogenous base or alkylolamine salts. These compounds are disclosed, among other places, in-the folowing United States Patents and copending applications: 2,026,785, 2,052,029, 2,053,653. application of Benjamin R. Harris, Serial No. 106,194, filed October 17, 1936; and application of Morris B. Katzman, Serial No. 125,931, filed April 9, 1937.

Again, in place of either the oxygenated phosphorus or oxygenated sulphur compounds, similar as well as corresponding oxygenated boron compounds may be employed. These include boric acid esters of higher molecular. weight alcohols such as lauryl borate, cetyl borate, and boric acid scription of such or similar compounds, reference may he made to United States Patent No. 2,052,192.

Another class of interface modifying agents whose solutions may be thickened in accordance with the principles of the present invention are the lower molecular weight sulphocarboxylic acid esters of higher molecular weightalcohols such as those described hereinabove. Among these compounds may be mentioned octyl sulphoacetate, lauryl sulphoacetate monoethanolamine or triethanolamine salt or other organic nitrogenous base salts such as those described hereinabove, cetyl potassium sulphoacetate, and the like. For a more complete description of such compounds, reference may be had to the following patents and co-pending applications: United States Patent No. 1,917,250; British Patent No. 377,249; United States applications of Benjamin R. Harris, Serial No. 627,096, filed July 30, 1932; Serial No. 34,840, filed August 5, 1935; Serial No. 121,563, filed Jan uary 21, 1937; Serial No. 174,655, filed November 15, 1937;' and the application of Frank J. Cahn and Morris B. Katzman, Serial No. 166,388, filed September 29, 1937.

Still another class of interface modifying agents whose solutions may be thickened in accordance with the teachings of the present invention are the compounds which correspond to the general formulae 1 R-o0-Nx ,(YM).

2 'liC--0-Y-M oxygenated sulphur-containing inorganic acid radical such as the like, and w is a small whole number. As illustrative of these compounds may be mentioned the following:

( CuHa-C O-NH-CaHr-SOrNu These compounds and others of similar nature are disclosed in the following United States Patents 1,981,792, 1,932,180, 1,931,540 and 1,932,177.

It will be understood that the radical R in theabove general formulae may be derived from higher aliphatic, fatty, cycloaliphatic, aromatic. and hydroaromatic acids such as. the following: caproic acid capric acid, saturated and unsaturated higher molecular weight aliphatic acids such as the higher fatty acids containing at least eight carbon atoms and including melissic acid, stearic acid, oleic acid, ricinoleic acid, linoleic acid, linolenic acid, lauric acid, myristic acid, palmitic acid, mixtures of any two or more of the above mentioned acids or other acids, mixed higher fatty acids derived from'animai or vegetable sources, for example, lard, coconut oil. sesame oil, corn oil, cottonseed oil, sardine oil, tallow, partially or completely hydrogenated animal and vegetable oils such as those mentioned; hydroxy and alpha-hydroxy higher aliphatic and fatty acids such as i-hydroxy stearicacid, droxystearic acid, alpha-hydroxy stearic alpha-hydroxy palmitic acid, alpha-hydroxy lauric acid, alpha-hydroxy coconut .01! mixedample, butyl naphthalene sulphonic acid and its salts such as the sodium salt, benzyl naphthalene sodium sulphonates and iso-propyl naphthalene sulphonates. Particularly contemplated are those polynuclear derivatives, such as those of naphthalene, which contain alkyl, arallqrl or hydroaromatic radicals with three carbon atoms and upwards. These compounds are, in general, disclosed in United States Patent No. 1,752,184. Another class of interface modifying agents whose solutions may be thickened in accordance with the teachings of the present invention are the quaternary ammonium'compounds which arerepresented by the general formula wherein R1 represents an aliphatic radical, such as a hydrocarbon radical or the radical of a polyhydric alcohol linked to an allqrl or acyl group in the form of an ester or an ether, in each case said aliphatic radical containing at least eight carbon atoms, Ra, Ba, and R4 are hydrogen or hydrocarbon groups which may be components of a heterocyclic ring, and X represents halogen or other anions such as OH-, HSOr, RSOF, CsI'BSOJ', borate. phosphate, nitrate, acetate. etc. Among the specific substances falling within this general class are cetyl, trlmethyl ammonium bromide or chloride, lauryl pyridinium bromide or iodide, cetyl pyridinium iodide, lauryl trimethyl ammonium chloride or iodide, mono-oleic acid ester of dlethylene glycol pyridinium chlo ride, octadecyl pyridinium bromide, octyl pyridinium chloride; 4 dodecyl, N-methyl-quinaldimummethylsulphate, N-ethyl triethanolamine monoto the sulphur through a-member of the group oieate-bromide, salts of higher molecular weight betaine esters, etc.

A'somewhat similar class ofquaternary ammonium compounds, which are interface modifying agents and whose solutions may be thickened in accordance with the teachings of this invention, is that disclosed in the patent to Benjamin R. Harris, No. 2,023,075. Among the compounds disclosed therein may be mentioned, for example, dodecyl ester of betaine chloride, cetyl ester of betaine chloride, octyl ester of betaine bromide, and cholesteryl ester of betaine bromide.

' Still another class of interface modifying agents whose solutions may be thickened by means of the thickening agents disclosed herein comprises the sulphonium and phosphonium compounds corresponding, in general, to the quaternary ammonium compounds previously disclosed. Among these compounds may be mentioned dodecyl dimethyl sulphonium. bromide, methyl butyl octadecyl sulphonium chloride, hexadecyl triethyl phosphonium bromide, and dodecyl trimethyl phosphonium bromide. For a more complete disclosure of this type of compound, reference may be had to United States Patent No. 2,061,621.

Other sulphonium compounds falling into the category of interface modifying agents whose solutions may be thickened are those compounds corresponding to the general formula wherein R1 is an aliphatic lipophile radical linked consisting of aliphatic ester and other derivatives of aliphatic polyhydroxy substances, R2 and Rs are'radicals oi the group consisting of alkyl, aryl,

aralbl, cyclic, heterocyclic, and almlol, Z is an anion, and n is a small whole number. As illustrative of such compounds, the following are listed:

0 O1 CHI-CH1 (R-- is the acyl radical of coconut oil mixed fatty acids commining predominately lam-lo acid) O CuHrE-O-CHa-C H2\ /0 Bil-C 8 HOCHaCg I groups, Z represents a lipophilic group, and Y represents a hydrophilic group such as hydroxyl,

sulphate, sulphonic, phosphate, phosphonic, and

Other compounds of this class are disclosed in the copending application of Benjamin R. Harris, Serial No. 157,949, filed August 7, 1937.

A further class of interface modifying agents whose solutions may be thickened by means of the thickening agents of the present invention comprises higher molecular weight carboxylic acids and derivatives thereof wherein at least one hydrogen attached to the carbon atom adjacent to the carboxyl group of said carboxylic acids is replaced by a radical having strong hydrophilic properties, particularly hydrophilic radicals comprising oxygenated sulphur and oxygenated phosphorus. Examples of such compounds are as follows:

( CHa-(G Ha)u-CH-C 0 ONE Other compounds falling into this category are disclosed in the copending application of Frank J. Cahn, Serial No.- 135,957, filed April 9,1937.

Again, the thickening agents of the present invention may be employed for thickening interface modifying agents which fall into the category of sulphonated triglyceride oils, the best known of which are the so-called Turkey red oils. The products are so well known as to require no further discussion or description.

Still another class of interface modifying agents whose solutions maybe thickened in accordance with the teachings of the present invention comprises compounds of the type disclosed in the United States Patent to Benjamin R. Harris, No. 2,025,984. These comprise esters of aliphatic lipophile carboxylic acids with aliphatic hydroxycarboxylic acids, the esters containing at least one unesterifled carboxyl group in the hydroxy carboxylic acid radical. Examples of such compounds are monostearic acid ester of citric acid, monolauric acid ester of malic acid', and monopalmitic acid ester of mucic acid.

If will, of course, be appreciated that the various thickening agents vary in their potency. The amount to be employed will accordingly be determined not only by this fact but also will be dependent upon the speciflc character and concentration of the interface modifying agent in the solution thereof, andQhe particular results desired. As illustrative, while, as indicated, the ratio of specific system into which such thickeners are introduced, in general the monoethanolamlne salts are of the order of about three to sometimes corresponding triethanolamine salts in their thickening power.

tency of specific thickeners may vary with the high as' about fifteen times the potency of the Interface modifier solution Addition agent Results 10 cc. of a 10% aqueous solution of trlethanolamine salt oi lauryl sulphoacetate.

10 cg. gt a 25% aqueous solution of trlethanolarnine salt oi lauryl sulp a e.

7 108033? a 10% aqueous solution of CuHu-CO-NH-OHr-Ollr- 10 cc. of a 40% aqueoussolution oi isopropylnaphthalene sulphonate,

sodium sal 10 cc. of a 25% aqueous solution of lauryl sulphate, triethanolamine sa 10Sc8Ii a 15% aqueous'solution oi CgHn-CO-NH-CHr-Cflz- 10 cc. of an aqueous solution oi rather low viscosity containing 2%%oi the triethanolaniine salt of laurylsulphoacetate and 106% oi triethanolarnine phosphate.

10 cc. of a 25% aqueous solution of sodium octylsulphate 5 cc. oi a 14% aqueous solution oi monoethanolamine salt of laurylsulphoacetate. 6 cc. of a 25% aqueous solution oi triethsnolsmine salt of lauryl sul- 1 gram monoethanolamine acetate.

2gmms monoethanolamine sul hate" Small amount oi monoethano ine acetate. Sm sh amount of diethanolamine ace 8. Brant]: amount oi triethanolamine are Small amount oi 1-amino-2, 3-propanediol acetate. Smallmainount of i, 2-diaminopropanol ace 0. Small anount of monoethanolamine ace amount oi diethanolamine ace- Small amount oi triethanolamine aceamoutnt of l-amino-z, 3-propaneaceta Small amount of 1,2-diamlnopropanol a i be' 1 ti i cc.o aqueonsao u ono monoethanolamine phosphate.

36 cc. oi a 60 0 aqueous solution oi triethanolain e hosphste.

55 cc. of a 0 aqueous solution oi 00.0 a aqueoussou ono ethanolamlne acetate. 2ce.oia50%aqueoussolutionoimonoethanolaxnine phosphate.

10 cc. of a 50% aqueous solution of monoethanolamine phosphate (neutral to litmus).

Several drops of a 50% aqueous solution of ethanolamine phosphate.

6 cc. Ma 50 aqueous solution oi ethylenediam esulphate. 2/10 cc. oi a 50% aqueous solution of bu tylamine acetate. o

5 8332;: aqueous solution of CnHn-CO-NH-ClIz-Oflaloal oziaa 15% aqueous solution of C17HuC-0-NHCHzCHg- 5 cc. of a 10% aqueous solution of lauryl pyridinium iodide 5 cc. of a 16% aqueous solution of 3 cc. oia 0 aqueous solution oiethylenediam e sulphate. 5 co. oi a 50% aqueous solution oi monoetlaanolamine phosphate. o

5 cc. of a 32% aquoeous solution of a tetraphosphate of CnHnC OCHr-CH:O-CHICHr-OH,

monoethanolamine salt cc. oi a 12% aqueous solution of 5 cc. oi a aqueous solution oimonoothanolen ilna sulphate.

Considerable increase invismslty.

Do. Appreciable thicken S] t but a preciable l clrenin Clear solution with increase in viscosity. Very viscous solution.

Considerable thicken- A preciable thicken- Considerable thickening.

Clear. thick solution.

Appreciahie increase in viscosity.

Considerable increase in viscosity.

thickener which may be employed is variable within relatively wide ranges of proportions, in order to indicate the remarkable and unusual aspects of this phase of the invention, the following fa of closed herein, even in concentrations as high as While, as stated and is obvious, the amount of cts should be understood. Aqueous solutions many of the thickening agents which are dis- 50 are of a very limpid character with viscosity practically identical with or not much greater than that of ordinary water. addition of relatively small proportions of such Nevertheless, the

limpid solutions to interface modifying agent so- While it is preferred to carry out the invention with respect to the thickening of aqueous solutions of the interface modifying agents, it must not be inferred that the invention is so limited. Alcoholic or other organic solvents may be employed, as well as aqueous-organic solvent mixtures, but for economic and other obvious reasons water is preferred.

The term "solution" as employed herein and in the appended claims is employed in a broad sense to include not only true solutions but also 001- loidal dispersions.

Sit

The term higher, as employed herein, is y a easos intended to mean not less than eight carbon atoms and, concomitantly, the term lower will be understood to mean less than eight carbon atoms, unless otherwise specifically stated.

The present application is a continuation-inpart of prior application, Serial No. 166,388, filed September 29, 1937...

The terms interface modifier and interface modifying agent are employed interchangeably herein and are intended to embrace substances, other than soap, which comprise lipophile and hydrophile -groups and which are capable of reducing surface and interfacial tension.-

Wl'iile the thickening eflect increases with increasing concentrations of interface modifying agents and while it commences to become appreciable,in most cases, at concentrations of the order of magnitude of several percent or live! to ten percent, nevertheless the invention is applicable, as well, at concentrations of interface modifiers substantially below and beyond the abovementioned range. Indeed, the invention is applicable to the treatment of solutions of interface modifiers of as low as about 0.5% strength and as high as'25% or 30% strength, or even higher,

What we claim as new and desire to protect by Letters Patent of the United States is:

l. A method of thickening a solution of an interface modifier having a lipophile group with at least eight carbon atoms and a hydrophile group, which comprises adding thereto a proportion of an inorganic acid salt of an organic nitrogenous base which is soluble in said solution suflicient to appreciably thicken the same.

2. A method of thickening a solution of an interface modifier having a lipophile group with portion of an inorganic acid salt of an alcohol amine which is soluble in said solution suilicient to appreciably thicken the same.

3. A method of thickening a solution of an interface modifier having a lipophile group with at least eight carbon atoms and a hydrophile group, which comprises adding thereto a proportion of an inorganic acid salt of monoethanolamine which is soluble in said solution sumcient l to appreciably thicken the same.

4. A method of thickening a solution of an interface modifier having a lipophile group with at least eight carbon atoms and a hydrophile roup, which comprises adding thereto a proportion of a salt of monoethanolamine with a strong inorganic acid which is soluble in said solution sumcient to appreciably thicken the 5. A method of thickening an aqueous solution of an interface modifier having a lipophile group with at least eight carbon atoms and a hydrophile group, which comprises adding thereto a proportion of monoethanolamine sulphate sufiicient to appreciably thicken the same.

6. A method of thickening an aqueous solution of an interface modifier having a lipophile group with at least eight carbon" atoms and a hydrophile group, which comprises adding thereto a water-soluble salt of an organic nitrogenous base with a water-soluble inorganic acid sufflcient to appreciably thicken the same.

'7. A solution of an interface modifier having a 'lipophile group with at least eight carbon atoms and a hydrophile group, containing a proportionof an inorganic acid salt of an organic nitrogenous base which is soluble in said solution sufficient to appreciably thicken the same.

8 An aqueous solution of an interface modifier having a lipophile group with at least eight carbon atoms and a hydrophile group, containing,

a-proportion of a water-soluble salt of an organic nitrogenous base with a water-soluble inorganic acid suiiicient to appreciably thicken the same.

9. A solution of an alkyl sulphate of higher molecular weight containing a proportion of an inorganic acid salt of an organic nitrogenous base which issoluble in said solution sufllcient to appreciably thicken the same.'

10. A solution of at least 5% of a salt of sulphuric acid ester of an aliphatic alcohol having from eight to eighteen carbon atoms and containing a proportion of a 'salt of an organic nitrogenous base with a water-soluble inorganic acid, which latter salt is soluble in said solution, sumcient to appreciably thicken the same.

11. A solution of an alkylolamlne salt of a sulphuric acid ester of a straight chain aliphatic alcohol having from eight to eighteen carbon atoms and containing a proportion of an inorganic acid salt of an organic nitrogenous base, which latter salt is soluble in said solution, sufficient to appreciably thicken the same.

12. A solution of an alkylolamine salt of lauryl sulphate and containing a proportion of a salt vof an organic nitrogenous base with a watersoluble inorganic acid, which latter salt is soluble in said solution, suiilcient to appreciably thicken the same.

13. An aqueous solution of at least 5% of an alkylolamine salt of the sulphuric acid ester of a mixture of alcohols derived from cocoanut oil and comprising predominantly lauryl alcohol, and containing a proportion of a salt of an organic nitrogenous base with sulphuric acid, which latter salt is soluble in said solution, sufliclent to appreciably thicken the same.

14. An aqueous solution of at least 5% of an ethanclamine salt of the sulphuric acid esters of a mixture of higher aliphatic alcohols derived from triglyceride oils or fats, and containing a proportion of an inorganic acid salt of an organic nitrogenous base, which latter salt is soluble in said solution, sumcient to appreciably thicken the same.

15. A solution of an interface modifying agent wherein R is an aliphatic hydrocarbon radical containing at least 7 carbon atoms and preferably between 11 and 17 carbon atoms, X is hydrogen, n is zero or one, Y is a lower molecular weight hydrocarbon radical, M is an oxygenated sulphur-containing inorganic acid radical, and w is a small whole number, and containing a proportion of an inorganic acid salt of an organic nitrogenous base, which latter salt is soluble in said solution, suflicient to appreciably thicken the same 16. An aqueous solution of at least 5% of an interface modifying agent having the general formulav wherein RCO is the acyl radical of a higher fatty acid containing 12 to 18 carbon atoms,

and Z is a cation, and containing a proportion of a salt of an organic nitrogenous base with a water-soluble inorganic acid, which latter salt is soluble in said solution, sufficient to appreciably thicken the same.

17. An aqueous solution of at least 5% of an interface modifier having a lipophile group with at least eight carbon atoms and a hydrophile group, having good sudsing and detergent properties, and containing a proportion-of a watersoluble salt of analkylolamine with a watersoluble inorganic acid sufficient to appreciably thicken the same.

18. An aqueous solution of at least 5% of an interface modifier having good sudsing and dc 'to appreciably thicken the same.

19., An aqueous solution oi at least 5% of an interface modifier having good sudsing and detergent properties and comprising an oxygenated sulphur derivative of an aliphatic lipophile material having at, least twelve carbon atoms.

and containing a proportion of a sulphuric acid salt of an organic nitrogenous base which is soluble in said solution suflicient to appreciably thicken the same.

20. A water solution containing at least several percent of an interface modifying agent having a lipophile group with at least eight carbon atoms and a hydrophile group, having good sudsing and detergent properties, and containing a thickening agent in the form of a water-soluble salt of a strong inorganic acid with an alkylolamine sufficient to appreciably thicken the same.

MORRIS B. KATZMAN. FRANK J. CAHN. 

